Support `diffsplit` in PR

[aghost-7]

Support `diffsplit` in PR

[AGhost-7]

To my knowledge, vimdiff only supports diffing one file at a time. Most PRs I review are multiple files.

[dzhang-b]

@AGhost-7 yeah, but it can be a queue of files to be reviewed. git difftools does that and it automatically opens the next file to be reviewed if you close the current diffs.

[AGhost-7]

Personally this isn't how I'd want to review a PR. I scan the whole changes first then look in higher detail each file. I don't think vim diff is going to work.

If you're interested in implementing this I would accept a PR as an opt-in feature (meaning the old behaviour would be the default).

[dzhang-b]

@AGhost-7 I found that in diff page I can type gf on the diff content and go to that file. It is very useful and I dont think this feature is needed for now. Thanks!